Pull-type information transmission wherein a user accesses a server device of an information provider from a communication terminal such as a personal computer or the like to download desired information has been known conventionally in the field of information providing services which use the Internet.
Additionally, push-type information transmission wherein information is provided to the user from the server side without awaiting access by a user has been proposed in recent years.
Communication networks have become more complicated and diversified of late, so that the forms of networks in which various routers exist between the server device and the user terminal such as by interposing a gateway device between networks with different protocols have also increased.